Glossary · Mechanism
Fusee
A tapered grooved cone that equalises mainspring torque through a chain or gut line.
Explanation
A fusee is a cone-shaped pulley connected to the mainspring barrel by a chain (in watches) or gut line (in clocks). As the spring runs down and its force weakens, the chain winds onto a wider part of the cone, increasing leverage and evening out the power delivered to the train. It was standard in good English pocket watches and chronometers until the 19th century, when better springs and the going barrel made it unnecessary in most watches.
In the object catalogue
Catalogued objects whose own source record mentions “Fusee”. The quoted line shows where; it is the seller’s or museum’s wording, not independent verification.
Movement
English fusee detached lever pocket watch movement by John Harrison, Liverpool
“English fusee detached lever pocket watch movement by John Harrison, Liverpool”
Clock
Tabernacle clock with hour striking and alarm movement
“According to the Fitzwilliam Museum, this German tabernacle clock features an hour striking and alarm movement housed in a case constructed primarily of copper gilt, accented wi…”
Clock
Benjamin Lewis Vulliamy Fusee Mantel Clock, No. 1874
“Benjamin Lewis Vulliamy Fusee Mantel Clock, No. 1874”
Pocket watch
Justin Vulliamy Gold Pair Cased Pocket Watch
“This 18th-century gold pair-cased pocket watch is reported by the auctioneer to date from London, 1778. The watch features a fusee cylinder movement signed 'Justin Vulliamy, Lon…”
Clock
Hunt & Roskell engraved carriage clock
“This miniature carriage or mantel clock measures approximately 14 cm in height and features an engraved gilt-brass rectangular case. According to the owner, it was originally pu…”
Pocket watch
Dent 18K Gold Pocket Chronometer with Original Box
“This mid-nineteenth-century open-face pocket chronometer is signed by Dent, London, and numbered 29216. Housed in a solid 18K gold case bearing London hallmarks for 1863 and the…”